Recovery of copper from solutions containing it.



PATENTED MAY 15, 1906.

13. COMBA. RECOVERY OF COPPER FROM SOLUTIONS CONTAINING IT.

APPLICATION FILED SEPT. 14. 1903.

2 SHEETSSHEET 1.

No. 820,555. PATBNTED MAY15V19O6.

' B. OOMBA. RECOVERY OF COPPER PROM SOLUTIONS CONTAINING IT.

APPLICATION FILED SEPT.14.1903.

2 SHEETS-SHEET 2.

Mina-sees P Inventor.

V 1 2 HQQZ PWK/ NITED STATES PATENT sFIoE.

BENVENUTO COMBA, OF TURIN, ITALY, ASSIGNOR TO EDWARD CASPER, OF LONDON, ENGLAND.

RECOVERY OF COPPEBJ'ZROM SOLUTIONS CONTAINING IT.

Specification of Letters Patent.

Patented May 15, 1906.

Application filed September 14, 1903. Serial No. 173.185.

To all whom it may concern:

Be it known that I, BENVENUTO UoMBA, a, subject of the King of Italy, residing at 40 Via Po, Turin, in the Kin dom of Italy, have invented new and usefu Improvements in the Recovery of Copper from Solutions Containing It and I do hereby declare that the following is a full, clear, and exact descri tion of the invention, which will enable ot ers skilled in the art to which it appertains to make and use the same.

r This invention relates to improvements in the process of precipitating copper from acid liquors containing itfor example, a solution of sulfate of copper obtained by lixiviations of roasted copper pyrites or iron pyrites con taining copperand which is effected by the substitution for the copper of another metal of less value, usually scrap-iron.

Now in lieu of immersing the precipitating metal in the cupreous liquor and recovering the copper in the form of an impure sludge containing on analysis from sixty to seventy per cent. of the copper from the solution in an impure stateI make use of an apparatus which in principle resembles a large Daniell cell, but without diaphragms, and in which the precipitating metal is separated from the cupreous liquor and is dlssolved without coming into contact with the copper, the said 3 copper being precipitated in apure state electrolytically upon sheets of copper or lead, preferably lead, and in such a ductile condition as to be ready for rolling.

To enable the invention to be fully understood, I will describe it by reference to the accompanying drawings, in which Figure 1 is a longitudinal section of suitable apparatus for carrying out the invention. Fig. 2 is' a partial transverse section thereof, and Fig. 3 is a partial plan view of the apparatus.

a is a Water-tight vat or bath of suitable shape and size and which may bent" wood, rubble, or brick, or other suitable material. Near the upper ed e of the vessel or bath a and above the level of t e cupreous liquor are fixed cross-pieces of wood I) I), supported upon the ledges c c, and upon these cross-pieces b b are suspended sheets d d of lead, (cleaned and then rubbed with powdered graphite-,) upon each side of which sheets the copper from the cupreous liquor is to be deposited.

If scrap-iron is used, a sheet e of copper gauze is placed upon'the upper ends of the metal sheets (1 d, upon which the scrap-iron f in any suitable form is placed. This'gauze e is caused by the weight of the iron to make contact with all the metal sheets (i, which are thus all laced in electric connection, so that they a remain in the same electrical condition during the operation of the apparatus. This gauze sheet, however, is only necessarywhen small pieces of old iro nsuch as nails, &c.are employed. If pig-iron or old rails or bars or large pieces of iron which can rest upon two' or three adjacent vertical sheets are employed, the said gauze is not necessary.

The iron and lead electrodes being arran ed in the vat or bath a, as above descri ed, slightly-acidulated warm water is introduced to a slight depth in the bottom of the bath, after which the cold cupreous liquor is gently admitted, this being efiected through a feed-tube g, which is inserted into a wide tube It, extending to the bottom of the bath, with which it communicates by the holes h h, the feed-tube g reaching nearly .to the level of these holes, so that the liquor is relieved of any air which it may contain before entering the bath. The liquor in rising up the bath a raises the warm water on;

account of the difference in their specific gravities, and when this warm acidulated water comes into contact with the iron scrap or the like. f the electrolytic action commences. The plane separating the acidulated water and the liquor will be observed to gradually drop as the li uor deposits itscopper upon the vertical. ead sheets and loses its color. Fresh liquor will then be automatically introduced below, as above described, and the operation can be regulated with facility in such a manner that the cupreous liquor is never allowed to come into contact with the upper precipitating metal. The spent liquor which'is gradually raised overflows at t and can be conveyed away for reuse and crystallization.

j is a pipe running around the vat a at the 1 upper part above the gauze e and throu h which steam is caused to circulate for t e purpose of maintaining the temperature of the acidulated water at the requisite'degree for efficient o oration.

The level 0 the cupreous solution is always a few centimeters below the contact be- .per parts of the plates tween the iron and the heads of the copper v current immediately on its generation is more intense and has less resistance offered to its flow. The precipitated copper diminishes in thickness from the said level downward .as the resistance increases with the iHath which the current must take in flowing om top to bottom of the cathodic plate.

The apparatus shown and described herein is not specifically claimed, as it will form the s'ubjectmatterof a separate application for Letters Patent of the United States.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim.is

1. The method of recovering copper from solutions containing it, which consists in placing the solution in a suitable vessel, immersing a cathode therein, superimposing a liquid of less specific gravity uponthe surface of the copper solution, and supporting an anode in said supernatant liquid, in direct contact with the cathode, whereby an electric current is generated and pure copper is deposited upon the cathode, substantially as described.

2. The method of recoverin copper from solutions containing it, whic consists in placing the solution in a suitable vessel i1nmersing a cathode therein prepared for the deposition of copper thereon, superimposing an acidulated liquid of less specific gravity than the copper solution, supporting an anode in said supernatant liquid out of con tact with the copper solution and in contact with the cathode, supplying additional cop per solution adjacent to thebottom of the solution in said receptacle, to maintain the line ofseparation between the liquids substantially constant and drawing off the excess of supernatant liquid, as the action progresses, substantially as described 3. The method of' recovering copper from solutions containing it, which consists in placing the solution in a suitable vessel, immersing a cathode therein, superimposing a liquid of less specific gravity upon the surface of the copper solution, and supporting an anode in said supernatant liquid and con necting it electrically with the cathode, and applying heat artificially to the supernatant liquid, substantially as described.

4. The method of recovering copper from solutions containing it which consists in placing the copper solution in a suitable receptacle, and immersing therein a cathode adapted to receive adeposition of copper thereon, superimposing acidulated water upon the copper solution and immersing iron in said acidulated water, out of contact with the copper solution and in contact with the cathode, substantially as described.

BEN V ENUTO COMBA. Witnesses:

EDWARD (JASPER, ETHEL W. RANKILOR. 

